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11 MAX FRQ (MAXIMUMFREQUENCY)

 Thisparameterdefinestheupperlimitofthedrive’sspeedrange.MAXFRQisusedinconjunctionwith

MINFRQ(Parameter10above)todefinetheoperatingrangeofthedrive.

  Consultmotormanufacturerbeforeoperatingmotoraboveratedfrequency.Overspeedingthe

motorand/ordrivenequipmentcancausedamagetoequipmentandinjurytopersonnel!

12 DC BRAKE (DCBRAKEVOLTAGE)

 DC braking creates a braking torque by injecting DC voltage into the motor. This parameter set the

magnitudeofthatDCvoltage.ThepointatwhichthedriveappliesDCbrakingtothemotordependson

whichSTOPmodeisprogrammed(eitherCOASTorRAMP,seeParameter26-STOP).

 IfthedriveissettoCOAST,DCbrakingisactivatedwhenthestopcommandisgiven.Inthiscase,DC

brakinghelpsdeceleratethemotor.Thisisusefulinapplicationswhereaquickdecelerationisdesiredona

loadthatwouldnormallytakealongtimetocoasttoastop.

 Ifthe drive is set to RAMP, DC braking is activated when the output frequency reaches 0 Hz. In this

case,thedrivedeceleratestheloadtoanearstopandthenDCbrakingisusedtostopandholdthemotor.

This is useful in applications where the load needs to be stopped in a certain position. Similar applications

with high-inertialoadsutilizeboth dynamic braking and DC braking. The dynamicbrakingallowsthe

high-inertialoadtobedeceleratedquickly,whiletheDCbrakingstopstheloadinthedesiredposition.

 Dueto heatgenerated inthemotor, DCbraking shouldonlybe usedinapplications wherethe loadis

stoppedinfrequently.Inhighduty-cycleapplications,dynamicbrakingisrecommendedbecausetheheatis

dissipatedthroughexternalresistorbanks,ratherthaninthemotor.Whenused,DCBRAKEshouldbeset

tothelowestvoltagethatprovidessatisfactoryoperationinordertominimizemotorheating.Themaximum

voltage available depends on the voltage rating of the drive. Refer to the table below:

13 DC TIME (DCBRAKETIME)

 Thisparameterdetermines thelength oftimethattheDC brakingvoltage isappliedtothemotor.DC

TIMEshouldbesetto thelowestvaluethatprovides satisfactoryoperationinorderto minimizemotor

heating.

NOTE:Ifthisparameterissetto999.9seconds(themaximumvalue),theDCbrakingwillbecontinuous.

If it is set to .0 seconds, it is disabled.

MAXIMUM DC BRAKE VOLTAGE

240/120 Vac 240/200 Vac 480/400 Vac 590/480 Vac

24 VOLTS 24 VOLTS 48 VOLTS 59 VOLTS

WARNING

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